Foldable display apparatus

ABSTRACT

A foldable display apparatus that is adjustable between a folded configuration and unfolded configuration includes a flexible display panel that is foldable; a case including a first case that supports a first side of the flexible display panel and a second case that supports a second side of the flexible display panel; a link member connecting the first case to the second; and a locking unit configured to prevent rotation of the first case and the second case in a folding direction when the foldable display apparatus is in the unfolded configuration.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to, and the benefit of, Korean PatentApplication No. 10-2015-0093232, filed on Jun. 30, 2015, in the KoreanIntellectual Property Office, the disclosure of which is incorporatedherein in its entirety by reference.

BACKGROUND

1. Field

One or more exemplary embodiments of the present invention relate to afoldable display apparatus.

2. Description of the Related Art

Flat-panel display apparatuses, such as organic light-emitting displaydevices, may be flexibly deformed, and thus may be made foldable so thatthey can be conveniently carried.

SUMMARY

One or more exemplary embodiments of the present invention include afoldable display apparatus.

Additional aspects are set forth in part in the description that followsand, in part, will be apparent from the description, or may be learnedby practice of the presented embodiments.

According to one or more exemplary embodiments of the present invention,a foldable display apparatus that is adjustable between a foldedconfiguration and an unfolded configuration includes a flexible displaypanel that is foldable; a case including a first case that supports afirst side of the flexible display panel and a second case that supportsa second side of the flexible display panel; a link member connectingthe first case to the second case; and a locking unit configured toprevent rotation of the first case and the second case in a foldingdirection when the foldable display apparatus is in the unfoldedconfiguration.

The locking unit may include a slide cover rotatably coupled to thefirst case and slidably coupled to the second case; and a locking leverrotatably mounted on the second case and configured to prevent slidingof the slide cover when the locking lever is in a locked position.

The slide cover may slide along a rail groove in the second case whenthe first case and the second case are rotated to move the foldabledisplay apparatus between the folded configuration and the unfoldedconfiguration. Rotation of the first and second cases may be inhibitedwhen movement of the slide cover along the rail groove is blocked.

A body center of the slide cover may be adjacent the link member whenthe foldable display apparatus is in the unfolded configuration, and thebody center of the slide cover may be moved toward the second case alongthe rail groove when the foldable display apparatus is moved from theunfolded configuration to the folded configuration.

The second case may define an insertion groove in a surface thereof andon which the slide cover and the locking lever are mounted.

The insertion groove may restrict a sliding range of the slide cover andmay restrict a rotating range of the locking lever.

The slide cover and the locking lever may be accommodated in a depth ofthe insertion groove.

The link member may include a concave-convex type metal sheet.

End surfaces of the concave-convex type metal sheet may be respectivelyattached to a first end surface of the first case and a second endsurface of the second case.

The foldable display apparatus may further include an elastic piececonnecting the first case to the second case.

The first case and the second case may each have a stepped surface, andthe elastic piece may be attached to the stepped surfaces of the firstcase and of the second case.

The flexible display panel may be outwardly exposed when the foldabledisplay apparatus is in the folded configuration.

A folded portion of the flexible display panel may be supported by thelink member when the foldable display apparatus is in the foldedconfiguration.

The link member may include a concave-convex type metal sheet.

The first case and the second case may each define a coupling groovecoupled to the flexible display panel.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects will become apparent and more readilyappreciated from the following description of the embodiments, taken inconjunction with the accompanying drawings, in which:

FIG. 1 is a perspective view of a foldable display apparatus accordingto one or more exemplary embodiments of the present invention;

FIG. 2 is an exploded perspective view of a case included in thefoldable display apparatus illustrated in FIG. 1;

FIGS. 3A-3B are rear surface perspective views respectively showing anunfolded state and a folded state of the foldable display apparatus ofFIG. 1;

FIGS. 4A-4D are side views sequentially showing a change in the state ofthe foldable display apparatus of FIG. 1 from an unfolded state to afolded state;

FIGS. 5A-5D are rear surface perspective views respectivelycorresponding to the processes of FIGS. 4A-4D; and

FIG. 6 is a cross-sectional view showing a detailed structure of aflexible display panel included in the foldable display apparatus ofFIG. 1.

DETAILED DESCRIPTION

As the present invention allows for various changes and numerousembodiments, particular embodiments are illustrated in the drawings anddescribed in detail in the written description. Hereinafter, aspects ofthe present invention and a method for accomplishing them are describedmore fully with reference to the accompanying drawings, in whichexemplary embodiments of the invention are shown. This invention may,however, be embodied in many different forms and should not be construedas limited to the exemplary embodiments set forth herein.

One or more embodiments of the invention are described below in moredetail with reference to the accompanying drawings. Unless otherwisenoted, like reference numerals denote like elements throughout theattached drawings and the written description, and thus, descriptionsthereof will not be repeated. In the drawings, the relative sizes ofelements, layers, and regions may be exaggerated for clarity.

It will be understood that, although the terms “first,” “second,”“third,” etc., may be used herein to describe various elements,components, regions, layers and/or sections, these elements, components,regions, layers and/or sections should not be limited by these terms.These terms are used to distinguish one element, component, region,layer or section from another element, component, region, layer orsection. Thus, a first element, component, region, layer or sectiondescribed below could be termed a second element, component, region,layer or section, without departing from the spirit and scope of thepresent invention.

The terminology used herein is for the purpose of describing particularembodiments and is not intended to be limiting of the present invention.As used herein, the singular forms “a” and “an” are intended to includethe plural forms as well, unless the context clearly indicatesotherwise.

It will be further understood that the terms “comprises,” “comprising,”“includes,” and/or “including” as used herein specify the presence ofstated features, integers, steps, operations, elements, and/orcomponents, but do not preclude the presence or addition of one or moreother features, integers, steps, operations, elements, components,and/or groups thereof. As used herein, the term “and/or” includes anyand all combinations of one or more of the associated listed items.

It will be understood that when an element or layer is referred to asbeing “on,” “connected to,” or “coupled to” another element or layer, itcan be directly on, connected to, or coupled to the other element orlayer, or one or more intervening elements or layers may be present. Inaddition, it will also be understood that when an element or layer isreferred to as being “between” two elements or layers, it can be theonly element or layer between the two elements or layers, or one or moreintervening elements or layers may also be present.

As used herein, the term “substantially,” “about,” and similar terms areused as terms of approximation and not as terms of degree, and areintended to account for the inherent deviations in measured orcalculated values that would be recognized by those of ordinary skill inthe art. Further, the use of “may” when describing embodiments of thepresent invention refers to “one or more embodiments of the presentinvention.” As used herein, the terms “use,” “using,” and “used” may beconsidered synonymous with the terms “utilize,” “utilizing,” and“utilized,” respectively. Also, the term “exemplary” is intended torefer to an example or illustration.

When a certain embodiment may be implemented differently, a specificprocess order may be performed differently from the described order. Forexample, two consecutively described processes may be performedsubstantially at the same time or performed in an order opposite to thedescribed order.

FIG. 1 is a perspective view of a foldable display apparatus accordingto one or more exemplary embodiments of the present invention.

The foldable display apparatus includes, as a display, a flexibledisplay panel 100 that is capable of being flexibly bent. The flexibledisplay panel 100 is a structure in which a thin film transistor and alight-emitting device for displaying an image, and an encapsulationlayer that covers and protects the thin film transistor and thelight-emitting device, are generally stacked on a flexible substrate.Because the flexible substrate is used instead of a rigid glasssubstrate, the flexible display panel 100 may be moved between a foldedor unfolded configuration (e.g., may be freely folded or unfolded)within an allowable flexibility range. Thus, in a folding state (e.g.,the folded configuration), the flexible display panel 100 may be foldedas shown in FIGS. 4D and 5D.

The flexible display panel 100 may be supported by a case 200 thatincludes first and second cases 210 and 220 such that the flexibledisplay panel 100 may be folded or unfolded. In other words, one end(e.g., a first end) of the flexible display panel 100 is accommodatedin, and supported by, a first coupling groove 210 a of the first case210, and another end (e.g., a second end opposite to the first end) ofthe flexible display panel 100 is accommodated in, and supported by, asecond coupling groove 220 a of the second case 220. Hereinafter,surfaces of the first and second cases 210 and 220, at the side of thefirst and second coupling grooves 210 a and 220 a on which the flexibledisplay panel 100 is mounted are referred to as front surfaces, andsurfaces on the opposite side of the first and second coupling grooves210 a and 220 a are referred to as rear surfaces.

The first and second cases 210 and 220 are connected to each other via alink member, for example, a ribbed (or concave-convex-type) sheet (e.g.,a metal sheet) 300. In other words, both ends of the concave-convex typemetal sheet 300 are attached to surfaces of the first and second cases210 and 220 that face each other, such that the first and second cases210 and 220 may be hinged. Accordingly, when the concave-convex typemetal sheet 300 is moved between being bent or unbent, the first andsecond cases 210 and 220 are folded or unfolded.

Elastic pieces 400 are attached on stepped surfaces 212 and 222 (seeFIG. 2) that are respectively formed on the first and second cases 210and 220, and thus the elastic pieces 400 connect the stepped surfaces212 and 222 to each other. The elastic pieces 400 help the first andsecond cases 210 and 220 collectively maintain a flat state when thefirst and second cases 210 and 220 are unfolded. In other words, whenbeing unfolded, the first and second cases 210 and 220 become flat in astraight or substantially straight line (see FIGS. 4A and 5A), and, whenthe first and second cases 210 and 220 are folded, the concave-convextype metal sheet 300 is bent, and thus the first and second cases 210and 220 are folded to overlap with each other (see FIGS. 4D and 5D). Theelastic pieces 400 secure (or hold) the first and second cases 210 and220 such that the flexible display panel 100 may properly maintain aflat state when being unfolded.

When the first and second cases 210 and 220 are in the unfoldedconfiguration, the case 200 should not be accidentally (orunintentionally) folded again in a folding direction. Thus, a slidecover 500 and a locking lever 600, for example, may be included aslocking units for preventing or inhibiting accidental (or unintentional)re-folding.

The slide cover 500 may be rotatably coupled to a rotational shaft 211formed on the first case 210, and may also be slidably coupled to a railgroove 221 formed in the second case 220. Thus, while the first andsecond cases 210 and 220 are folded or unfolded, the slide cover 500slides along the rail groove 221 while rotating about the rotationalshaft 211. In other words, the rail groove 221 is provided as a pathalong which the slide cover 500 may move during a rotating operation forfolding or unfolding the first and second cases 210 and 220, and, whenthe slide cover 500 does not move (or is hindered from moving) along therail groove 221, the first and second cases 210 and 220 enter a lockingstate in which the first and second cases 210 and 220 cannot rotate.

The locking lever 600 inhibits or stops rotation of the first and secondcases 210 and 220, namely, inhibits or stops re-folding of the first andsecond cases 210 and 220, by preventing or inhibiting (e.g., selectivelypreventing) movement of the slide cover 500. The locking lever 600 isrotatably mounted on a rear surface of the second case 220.

FIGS. 3A and 3B respectively illustrate the foldable display apparatusaccording to one or more embodiments of the present invention in alocked configuration and an unlocked configuration according to movementof the locking lever 600 and the slide cover 500.

Referring to FIG. 3A, the locking lever 600 may rotate in a directionindicated by arrow A on the second case 220, and the slide cover 500 mayslide in a direction indicated by arrow B. However, when the lockinglever 600 has been rotated to be substantially perpendicular to theslide cover 500 as illustrated in FIG. 3A, the slide cover 500 may notmove. In other words, if the locking lever 600 is not utilized, theslide cover 500 may move along the rail groove 221 because a path ofmovement of the slide cover 500 is not blocked. However, in a state (orconfiguration) as shown in FIG. 3A, because the locking lever 600 blocksthe moving path of the slide cover 500, the slide cover 500 is unable tomove. When the first and second cases 210 and 220 rotate in a foldingdirection, the slide cover 500 naturally moves along the rail groove221. However, when the slide cover 500 is unable to move, the first andsecond cases 210 and 220 are unable to rotate. In other words, the firstand second cases 210 and 220 are locked such that the first and secondcases 210 and 220 may not be folded again from an unfolded state whenthe cover 500 is unable to move.

However, when the locking lever 600 is released from a locking positionby being at least slightly rotated, as shown in FIG. 3B, the slide cover500 is able to move along the rail groove 221 while also pushing (orfurther rotating) the locking lever 600, and thus the first and secondcases 210 and 220 are able to be folded in a direction indicated byarrow C. An insertion groove 223 may be formed in the rear surface ofthe second case 220. The slide cover 500 and the locking lever 600 areinserted (or accommodated) in the insertion groove 223, and thus do notprotrude outward from a surface adjacent to the slide cover 500 and thelocking lever 600. As illustrated in FIGS. 3A and 3B, the insertiongroove 223 restricts a sliding range of the slide cover 500, andrestricts a rotating range of the locking lever 600 to the area of theinsertion groove 223.

During folding, the first and second cases 210 and 220 are folded in adirection such that the flexible display panel 100 is exposed outwardly(see FIGS. 4D and 5D). During folding, a folded portion of the flexibledisplay panel 100 is supported by the link member, for example, theconcave-convex type metal sheet 300. Because the folded portion isstably supported according to a curvature of the concave-convex typemetal sheet 300 even when an external force is applied to the foldedportion, the folded portion is neither easily wrinkled nor deformed.

Folding and unfolding operations are described in more detail below.Turning now to an internal structure of the flexible display panel 100,the flexible display panel 100 may have, for example, a structure asshown in FIG. 6. In other words, a thin film transistor 121 and anorganic light-emitting device 122 are included in the flexible displaypanel 100, and the organic light-emitting device 122 includes anemission layer 122 b that is vulnerable to, particularly, contact withgas. In more detail, an active layer 121 f is formed on a buffer layer121 a that is adjacent to a flexible substrate 123, and the active layer121 f has source and drain regions doped with N-type or P-typeimpurities at a high concentration. The active layer 121 f may includean oxide semiconductor. For example, the oxide semiconductor may includean oxide of a material selected from the group consisting of Groups 4,12, 13, and 14 metal elements, such as zinc (Zn), indium (In), gallium(Ga), stannum (Sn), cadmium (Cd), germanium (Ge), hafnium (Hf), and/or acombination thereof. For example, the active layer 121 f may includeG-I-Z-O [(In₂O₃a(Ga₂O₃b(ZnO)c], wherein a, b, and c are integers thatrespectively satisfy a≥0, b≥0, and c>0. A gate insulating layer 121 b isformed on the active layer 121 f, and a gate electrode 121 g is formedon the gate insulating layer 121 b. A source electrode 121 h and a drainelectrode 121 i are formed on the gate electrode 121 g. An interlayerinsulating layer 121 c is included between the gate electrode 121 g andeach of the source electrode 121 h and the drain electrode 121 i, and apassivation layer 121 d is interposed between an anode 122 a of theorganic light-emitting device 122 and each of the source electrode 121 hand the drain electrode 121 i.

The organic light emitting device 122 includes an insulativeplanarization layer 121 e (e.g., a pixel defining layer), which mayinclude acryl, for example, on the anode 122 a, and also includes anaperture 122 d that is formed in the insulative planarization layer 121e.

The organic light-emitting device 122 displays an image (e.g.,predetermined image information) by emitting red, green, and blue lightas current flows therethrough. The organic light-emitting device 122includes the anode 122 a, which is connected to the drain electrode 121i of the thin film transistor 121, and to which a positive power voltageis applied, includes a cathode 122 c, which is formed to cover theentire pixel, and to which a negative power voltage is applied, and alsoincludes the emission layer 122 b, which is disposed between the anode122 a and the cathode 122 c to emit light.

A hole injection layer (HIL), a hole transport layer (HTL), an electrontransport layer (ETL) and an electron injection layer (EIL), forexample, may be stacked adjacent to the emission layer 122 b.

For reference, the emission layer 122 b may be formed in each pixel toform a single unit pixel that includes pixels that emit red, green, andblue light beams. The emission layers 122 b formed in the pixels may bespaced apart from one another. Alternatively, an emission layer may becommonly formed over the entire pixel region, regardless of locations ofthe pixels. In this case, the emission layer 122 b may be formed bystacking a light-emitting substance that is configured to emit a redlight, a light-emitting substance that is configured to emit a greenlight, and a light-emitting substance that is configured to emit a bluelight on one another, or by mixing a light-emitting substance that isconfigured to emit a red light, a light-emitting substance that isconfigured to emit a green light, and a light-emitting substance that isconfigured to emit a blue light. Any combination of other various colorsthat is capable of emitting white light may be utilized in addition to,or as an alternative to, a combination of red, green, and blue colors.The flexible display panel 100 may further include a color convertinglayer or a color filter that converts the white light into a light of acorresponding color.

In other embodiments, a thin film encapsulation layer, in which anorganic layer and an inorganic layer are alternately stacked on oneanother, may be additionally formed on the cathode 122 c.

Because the flexible display panel 100 is flexibly deformable, theflexible display panel 100 may be used while being folded or unfoldedaccording to folding and unfolding operations of the case 200.

A foldable display apparatus as described above may be used as shown inFIGS. 4A-4D and FIGS. 5A-5D. FIGS. 4A-4D are side views sequentiallyshowing a change in the state of the foldable display apparatus from anunfolded state/configuration to a folded state/configuration. FIGS.5A-5D are rear surface perspective views respectively corresponding tothe processes of FIGS. 4A-4D.

First, when the foldable display apparatus is in an unfoldedconfiguration where the foldable display apparatus is flat orsubstantially flat, the first case 210 and the second case 220 areunfolded to form a straight or substantially straight line, as shown inFIGS. 4A and 5A.

At this time, the locking lever 600 is in a state of blocking the slidecover 500 from moving along the rail groove 221. In other words, becausethe locking lever 600 blocks a moving path of the slide cover 500, theslide cover 500 is unable to move, and, as described above, the firstand second cases 210 and 220 are also unable to move or rotate. Thus,the unfolded state in which the first and second cases 210 and 220 areunfolded to form a straight line is maintained. Accordingly, a user isable to view a plane image via the flexible display panel 100 that isunfolded to be flat.

When the foldable display apparatus is stored or carried, for example,the locking lever 600 may be released, and the case 200 may be folded.To fold the case 200, when the locking lever 600 is slightly rotated, asshown in FIGS. 4B and 5B, the slide cover 500 is able to move along therail groove 221 while pushing or further rotating the locking lever 600,and thus the first and second cases 210 and 220 are folded in a foldingdirection.

The first and second cases 210 and 220 may be folded past an angle of 90degrees, as shown in FIGS. 4C and 5C, and may be folded to overlap witheach other, as shown in FIGS. 4D and 5D. In this case, the flexibledisplay panel 100 is outwardly exposed. Thus, even when the flexibledisplay panel 100 is folded, a user may view an image displayed on theflexible display panel 100. Because the folded portion of the flexibledisplay panel 100 is stably supported by the concave-convex type metalsheet 300, the folded portion is neither easily wrinkled nor deformed byan external force.

In the unfolded configuration, as shown in FIGS. 4A and 5A, a center CLof the body of the slide cover 500 is located at an area adjacent theconcave-convex type metal sheet 300. However, in the foldedconfiguration, as shown in FIGS. 4D and 5D, the center CL of the body ofthe slide cover 500 is moved to be at an area adjacent the second case220.

On the other hand, when display apparatus is moved from the foldedconfiguration to the unfolded configuration, the above-described processduring folding is conducted in reverse order. When the unfolding hasbeen completed, the locking lever 600 is rotated, as shown in FIGS. 4Aand 5A, to prevent or inhibit the slide cover 500 from moving, and thusthe unfolding state is stably maintained. Thus, a flat state of thedisplay apparatus may be maintained (e.g., firmly maintained), and astable plane image may be displayed.

Therefore, when the foldable display apparatus according to one or moreexemplary embodiments of the present invention is folded, the foldabledisplay apparatus may stably support a folded portion of a flexibledisplay panel without wrinkling or breaking, and thus damage to theflexible display panel may be prevented, or the likelihood thereof maybe reduced. When the foldable display apparatus is unfolded, theflexible display panel may be firmly maintained in a flat state, andthus a stable plane image may be displayed.

It should be understood that the exemplary embodiments described hereinshould be considered in a descriptive sense only and not for purposes oflimitation. Descriptions of features or aspects within each embodimentshould typically be considered as available for other similar featuresor aspects in other embodiments.

While the present invention has been particularly shown and describedwith reference to exemplary embodiments thereof, it will be understoodby those of ordinary skill in the art that various changes in form anddetails may be made therein without departing from the spirit and scopeof the present invention as defined by the following claims and theirequivalents.

What is claimed is:
 1. A foldable display apparatus that is adjustablebetween a folded configuration and an unfolded configuration, thefoldable display apparatus comprising: a flexible display panel that isfoldable; a case comprising: a first case that supports a first side ofthe flexible display panel; and a second case that supports a secondside of the flexible display panel; an elastic piece connecting thefirst case to the second case, the elastic piece being substantiallyflat in the unfolded configuration; a link member connecting the firstcase to the second case and comprising a concave-convex type single bodymetal sheet; and a locking unit configured to prevent rotation of thefirst case and the second case in a folding direction when the foldabledisplay apparatus is in the unfolded configuration.
 2. A foldabledisplay apparatus that is adjustable between a folded configuration andan unfolded configuration, the foldable display apparatus comprising: aflexible display panel that is foldable; a case comprising: a first casethat supports a first side of the flexible display panel; and a secondcase that supports a second side of the flexible display panel; a linkmember connecting the first case to the second case; and a locking unitconfigured to prevent rotation of the first case and the second case ina folding direction when the foldable display apparatus is in theunfolded configuration, the locking unit comprising: a slide coverrotatably coupled to the first case and slidably coupled to the secondcase; and a locking lever rotatably mounted on the second case andconfigured to prevent sliding of the slide cover when the locking leveris in a locked position.
 3. The foldable display apparatus of claim 2,wherein the slide cover slides along a rail groove in the second casewhen the first case and the second case are rotated to move the foldabledisplay apparatus between the folded configuration and the unfoldedconfiguration, and wherein rotation of the first and second cases isinhibited when movement of the slide cover along the rail groove isblocked.
 4. The foldable display apparatus of claim 3, wherein a bodycenter of the slide cover is adjacent the link member when the foldabledisplay apparatus is in the unfolded configuration, and wherein the bodycenter of the slide cover is moved toward the second case along the railgroove when the foldable display apparatus is moved from the unfoldedconfiguration to the folded configuration.
 5. The foldable displayapparatus of claim 2, wherein the second case defines an insertiongroove in a surface thereof and on which the slide cover and the lockinglever are mounted.
 6. The foldable display apparatus of claim 5, whereinthe insertion groove restricts a sliding range of the slide cover andrestricts a rotating range of the locking lever.
 7. The foldable displayapparatus of claim 5, wherein the slide cover and the locking lever areaccommodated in a depth of the insertion groove.
 8. The foldable displayapparatus of claim 1, wherein end surfaces of the concave-convex typemetal sheet are respectively attached to a first end surface of thefirst case and a second end surface of the second case.
 9. The foldabledisplay apparatus of claim 1, wherein the flexible display panel isoutwardly exposed when the foldable display apparatus is in the foldedconfiguration.
 10. The foldable display apparatus of claim 9, wherein afolded portion of the flexible display panel is supported by the linkmember when the foldable display apparatus is in the foldedconfiguration.
 11. The foldable display apparatus of claim 1, whereinthe first case and the second case each define a coupling groove coupledto the flexible display panel.
 12. The foldable display apparatus ofclaim 1, wherein the elastic piece comprises a first elastic piece and asecond elastic piece in parallel with each other.
 13. A foldable displayapparatus that is adjustable between a folded configuration and anunfolded configuration, the foldable display apparatus comprising: aflexible display panel that is foldable; a case comprising: a first casethat supports a first side of the flexible display panel; and a secondcase that supports a second side of the flexible display panel, thefirst case and the second case each having a stepped surface; an elasticpiece connecting the first case to the second case, wherein the elasticpiece being attached to the stepped surfaces of the first case and ofthe second case; a link member connecting the first case to the secondcase and comprising a concave-convex type single body metal sheet; and alocking unit configured to prevent rotation of the first case and thesecond case in a folding direction when the foldable display apparatusis in the unfolded configuration.